Multiple station center drive crankshaft lathe



June 30, 1953 H. J. SIEKMANN ET'AL 2,643,570

MULTIPLE STATION CENTER DRIVE CRANKSHAFT LATHE Filed March 13, 1950 8 Sheets-Sheet l IN VEN TORS.

" HAROLD J. SIEKMA/VN AND WAL Z'ER R. MEYER RQMGLA A 7' TORNE Y.

June 30, 1953 H. J. SIEKMANN ETAL 2,643,570

MULTIPLE STATION CENTER DRIVE CRANKSHAFT LATHE Filed March 13, 1950 a Sheets-Sheet 2 IN VEN TORS.

m HAROLD J. SIEKMANN WAL TER R. MEYER MAM A TTOR/VEY.

June 30, 1953 H. .1. SIEKMANN ETAL I 2,643,570

' mum: sm'nou CENTER DRIVE CRANKSHAFT LATHE Filed March 15, 1950 I .a Sheets-Sheet 3 INVENTORS.

HAROLD .1. SIEKMAINN AND WAL TER R. MEYER A TTORNEY- June 30,1953 H. J. SIEKMANN ETAL 2,643,570

' MULTIPLE STATION CENTER DRIVE CRANKSHAFT'LATHE Filed March 13, 1950 8 Sheets-Sheet 4 IN VEN TORS.

HAROLD J. SIEKMA/VN Ann WALTER R- MEYER ibmu m A T TORNEY.

H. J. SIEKMANN ETAL June 30, 195.3

MULTIPLE STATION CENTER DRIVE CRANKSHAFT LATHE Filed March 13, 1950 8 Sheets-Sheet 5 INVENTORS. HAROLD J. S/EKMAN/V AND WALTER R. MEYER A T TORNE).

June 30,- 1953 H. J. SIEKMANN ETAL 2,643,570

. MULTIPLE STATION CENTER DRIVE CRANKSHAFT LATHE I Filed March 13, 1950 i 8 Sheets-Sheet 6 C /q v I -TR W In FIG.5 I

i 13 I I 4% 11 Q0 v I 17 11 w I H1 1 1m 87 m? 1 6% i l w I 4 l 43 v I, l

82, H g i W INVENTORS.

HAROLD J. S/EKMANN AND WALTER R. MEYER FIG? UMMSM June 30, 1953 H. J. SIEKMANN ETAL 2,643,570

MULTIPLE STATION CENTER DRIVE CRANKSHAF'I' LATHE Filed March 15, 1950 a Sheets-Sheet 7 IN VEN TORS. HAROLD J. S/EKMANN WALTER RMEYER June 30, 1953 H.. J. SIEKMANN ETAL 2,643,570

- MULTIPLE STATION CENTER DRIVE CRANKSHAFT LATHE Filed March 13', 1950 a Sheets-Sheet a IN VEN TORS. HAROLD J. S/EKMANN AND WAL TER RMEYER Sm gm ATTORNEY.

Patented June 30, 1953 MULTIPLE STATION CENTER DRIVE CRANKSHAFT LATHE Harold J. Siekmann and Walter. R. Meyer, Cincinnati, Ohio. assignors to The RP K. Le Blond Machine. Tool 00.,. Cincinnati, Ohio,. a. corporationof Delaware Application March 13, 1950, Serial No. 149 394 3 Claims; (Cl. 822.7)

1. This invention pertains to machine tools for the machinin of the" line bearings of multithrow internal combustion engine crankshafts More particularly, this invention is directed to the simultaneous machining of all of the line bearings of such crankshafts in a continuous manner in a multiple station type center drive crankshaft lathe;

One of the objects of this invention is to provide an improved method and apparatus for loading and unloading crankshafts in a machine tool for turning all of the line bearing portions simultaneously so as to reduce the loading and unloading timetoaminimum.

Another object of this invention is to provide an arrangement for automatically loading and unloading crankshaft'sin a multiple station cen ter drive crankshaft Iathe so that the operators effort is reduced tosimply locating and chucking the crankshaits' in the center drive lathe units in such a manner that the work pieces need not at any time be lifted by the operator.

Still another object of this invention is to providea multiple station center drivelathe having a single operatorsstation where the operator positions and clamps the work crankshaits in the center drive chucks or removes the crankshaits therefrom, the-machine being. arranged to automatically present unfinished: cranksha-its. for chucking and unchucki'ng in working position in the lathe units at theoperators station-,. and to" automatically remove finished crankshafts from the lathe units.

A further object isto provide a series ofcenter drive crankshaft lathes: on. an indexing. table so as to successively present each oi said lathes to a work receiving station, a chucking station, and a work unloading station in an automatically operating sequence.

Another object istoproiri'de at multiple station center drive l'athewith a Work. loading. station and a work unloadingv station and; an operators chucking station located. intermediate said loading and unloadin stations to facilitate arapid and continuous operation of the machine in turning the line bearings of a crankshaft.

Another object is to provide a multiple station center drive lathe with radially shiitable tailstocks and work receiving rails on said tailstoc'ks which automatically receive unmachined crankshafts and discharge finished machined crankshafts as the lathe indexes toa series oi work stations and an operators chucking station to provide a continuous machining operation on the line bearings of the cranks-hafts,

A further object is to provide a novel loading arrangement for automatically presenting workpieces tothe receiving: rails of the shifting tailstocks of the center drive lathe units and for automatically removing the finished workpiecestherefrom during a continuous machining operation of thelathe units on workpieces in the machine.

And another. object is'to provide an improved.

swinging supplemental supporting and guidev rail to facilitate axial positioning of the crankshafts in the center drive: ring gears at the operators chucking station.

Further features andadvantages of this invention will appear from the following detailed description of the. drawings in which;

Figure 1 is a front elevation of a machine incorporating the features of this invention.

Figure 2' is a plan. view ofthe machine of. Figure 1.

Figure'fia isa fragmentary section onthe line 2a2a of Figures 1 and 3.

Figure 3 is a diagrammatic transverse sectional view on the line 3--3 of Figure 2, particularly showing the indexing table mechanism and the tool feeding mechanism for the cutting tool of the center drive lathe units.

Figure 4 is an enlarged fragmentary sectional View onthe line 4-4- of Figure 2, particularly showing the loading track mechanism.

Figure 5 is; an enlarged; frag entary sectional view on the line 5-5 of Figure l and 2, particularly showing a right hand end view of a center drive lathe unit at the chucking and unchucking station.

Figure 6 is an enlarged fragmentary sectional view on the line 6--6 of Figure l and 2, particularly showing the center drive chucking mechanism and supplemental guide rail mechanism Figure '7 is an enlarged fragmentary sectional view on the line 1-? of. Figure 6, showing a portion of the supplementalv guide rail mechanism.

Figure 8 is an enlarged fragmentary sectional view on the line 8-8-o-f Figure 2, showing the unloading. track. mechanism.

A. machine incorporating the features of this invention comprises a circular base iii, Figure 3', having a central trunnion member H: fixedto the base by screws l2. A rotating and indexing table 1.3- is j ournaled on suitable bearings it supported by the trunnion member It. The table is also journaled on an annular bearing I5 on the base [0. The table" is rotated to desired indexed. positions by a hydraulic motor It having a drive shaft ll upon which is fixed the bevel. pinion. l8

driving the bevel gear I9 on the shaft 20. The shaft 29 is connected through suitable gearing 2| to drive the pinion shaft 22 having the pinion 23 which meshes with the large annular gear 24 fixed to the table I3 so that energizing the motor !6 causes rotation of the table I3. A brake and clamping mechanism is provided comprising a lever arm 25 pivotally mounted on the pivot pin 2-5 carried on the forked member 2! fixed to the base I0. This lever 25 has one end 28 arranged to engage the hardened ring 29 on the table I3 while its other end 39 is actuated by the hydraulic actuating plunger 3| in turn connected through the piston rod 32 to the actuating piston 93 in the cylinder 34. An indexing plunger 35 reciprocatably mounted in the base I of the machine is connected through the piston rod 36 to the actuating piston 31 in the cylinder 38 so a to precisely locat the table in desired indexed positions, the indexing plunger dropping into suitable indexing notches 39 formed in the ring gear 24. The hydraulic motor I6 and the cylinders 3s and 38 may be controlled in a desired sequence by any well known hydraulic and electrical control apparatus. Since the details of such apparatus forms no specific part of this invention, it will not be described herein.

On the tabl I3 is mounted a series of four double center drive crankshaft lathe units, A, B, C and D, Figure 2. Each of these units are identical so that a description of one will sufiice for all the others. Each of these units are constructed in a manner as fully set forth in Patent 2,069,107 issued January 26, 1937, comprising a supporting housing member 40, Figure 3, secured to the table l3 by screws 4!. Fixed to the supporting housing 40 are a pair of center drive housings 42 in which is journaled the center drive ring gears 43 which are driven through the center drive gear 44, the idler gear 45, and gear 46, from the drive shaft 41. The shaft 41 is connected to be driven through change gearing 48 and 49 from the main driving pulley 50 which in turn is driven from the main driving motor having the motor pulley 52 and the belts 53.

Each side of and between the center drive housings 42 are the tool carrier units 54 each of which contains the upper and lower tool bars 55 and 56, Figure 3, on the outer ends of which are mounted the tool blocks 51 and 58 containing th cutting tools T for machining all of the line bearing portions on the work crankshaft W. The tool bars are reciprocated by the feed crankshaft 59 through the connecting rods 69, the feed crankshaft being actuated through the segmental gear 6! which is in mesh with the rack bar 62 having the cam roller 63 which engages the feed cam plate 64 slidably mounted in the sup porting housing 40. The cam plate 64 is actuated by the feed screw 65 which is journaled against axial movement on the housing 40 and operates in the nut 66 fixed to the cam plate 64. The screw 95 is driven through a suitable disengageable feed clutch 61 from the gearing 68, 69, i0 and II, and the gear I2 fixed on the drive shaft ll. Rapid traverse driving power for actuating the feed screw 65 is derived from the rapid traverse motor 13 which is connected through the motor pulley 14, the belts I5, and the pulley 16 fixed to the feed screw 65. All of this apparatus is fully disclosed in the aforementioned Patent 2,069,107, so that further detailed description of this mechanism is not further required in this specification.

The crankshaft W to be machined are preferably provided with axially extending V-shaped locating notches or areas TI on the periphery of the rough webs of the crankshaft, such for example as shown in Patent 2,197,076, issued April 16, 1940. As best seen in Figure 6, the crankshaft is located in the center drive ring'gears 43 on the fixed locating block I8 secured to the'segmental member I9 of th chuck by screws 80, the segmental member in turn being fixed in th bore 8| of the ring gear 43. A clamping member 82 is pivotally mounted at 83 in the member 19 and has a locating block 84 fixed thereto by screws 85, the block 84 engaging the diametrically opposite notches T! on the crankshaft from the notches 'I'I engaged by the block I8. The other end of the clamping member 82 is provided with a clamping eccentric 86 having a wrench socket 81 by which the operator may clamp and unclamp the chuck. The eccentric 86 operates against the clamping block 88 which in turn engages the abutment block 89 fixed to the member "I9. A spring urged plunger 90 engaging the face 9| of the member I9 serves to move the clamping member 82 away from the work crankshaft W when the eccentric 86 is loosened.

The crankshaft W is supported on its ends by centers 92 which are carried in left hand tailstock TL and right hand tailstock TR which are arranged to be shifted radially of the axis of rotation 93 of thecenter drive ring gears on suitable guideways 95 by suitable hydraulic cylinder 94 on the tailstock base member 96 in a manner as fully set forth in Patent 2,211,722, issued August 13, 1940. Each of the tailstocks is provided with a work receiving rail 9? fixed in a bracket 98 secured to the front face of the tailstock by the bolts 99. The tailstocks are arranged to shift radially from a position with the centers 92 on the ring gear axis 93 to an opera tive position for the receiving rails 91 where a workpiece W, supported by the V-notches TI on the rail 91, has its main axis of rotation 93a positioned on the ring gear axis 93. When the workpiece or crankshaft W is in the latter position, it may be readily slid axially on the rails 91 into or out of the center drive chucking devices.

In order to facilitate the easy sliding of the workpiece crankshafts W into and out of the center drive chucks as above described, a series of supplemental swinging guide rails IOI, I02 and I03 are provided, Figures 6 and 7. The rails I III and I03 are located between the tailstocks and the center drive housings 42 while the rail I02 is located between the two center drive housings 42. These rails IOI, I02 and I03 are each respectively carried on the swinging arms I04, I05 and I06 which are fixed to the rock shaft I01 journaled in suitable bearings I08 in the center drive housings 42. These rails may swing from a position I09 for guiding the crankshafts into and out of the chucks to a retracted position IIO where the swinging arms have swung down against the stop pins I II fixed in the center drive housings 42. During the cutting operation the swinging rails normally remain in this position IIO out of the way. After the cutting operation has been completed and the tool bars and tool blocks have returned to retracted position 5811, the operator manually swings the rails IN, I 02 and I03 upwardly to the position I09. The rails are held in this position by a latching means comprising lever arms II2, Figure 6, formed integral with the swinging arm I05, on the outer ends of which is pivotally mounted the bellcran-kpawl H3 on the pin H4. The arm II3a of the pawl H3 is normally resiliently held against the stop pin H5 fixed in the arm I05 by a tension spring- I-IB connected between the pin II'I' fixed in the outer end of the arm II 3a and the cross pin I I8 in the swinging lever I05. The outer end of the arm- II3b of the bellcrank II3 has a latch surface II9- which engages behind the surface I-'of' thet'ool block 58 located between the center drive chuck housings 42 and has a stop surface I2I' to hold the latch in proper position with the tool block in retracted. position 5811. A further stopsurface I22 on. the. projection I23 ofthe swinging arm I05 engages: the surface I24 of the tool block 58 and a ten sion spring I25 interconnected between the pins. III and H8 serves to hold therails I'0I', I02 and I03 in swung-up position I09. It. will be noted that the rails IOI, I02 and I03 are clear of the crankshaft when the crankshaft is properly axially located in the center drive chucks. so that the chucks and ring gears may berot'ated at this timewith the rails in swung-up position I09. As soon as the cutting tools are started to traverse from retracted position 58av into thework crankshaft W, the surface II9 of the latch II3 slips past the edge I26 of the toolv block 58. to allow the rails I01, I02 and [03 to be swung back down towithdrawn position H0.

The rough unmachined crankshaft WF; Figure. 4, are placed on the: downwardly and. inwardly inclined loading track I2'I comprising a pair. of rails I26 and I29 which is reciprocatable. on suitable guideways I30 on the loading frame IL3I fixed to the floor upon which. the machine base I0 rests. The rails are reciprocat'ed by means of the fiuid' pressure operated cylinder I32 fixed. to the frame I3I by bolts I33. The cylinder I32 has a piston rod I34. connected through a link I35 to an actuating lever I36 pivotally mounted at I31 on the frame. I3I. The upper portion of the lever has an elongated slot I30 engaging around the pin I39 fixed. to the rails I28 and I29 so that by appropriate application. of fluid. pressure to the cylinder I32, the reciprocation of the rails I28 and I29 is effected. The rails are arranged to slope downwardly toward the right hand tailstockv TR of a center drive lathe unit when indexed to the unfinished work loading station R to receive rough workpieces WR.

A trip stop I40 having three projecting arms I4I, I42 and I43is pivotally mounted at I44 on the inner end of the rails I28 and I29. The rails I28 and I29 are normally: held in retracted position by the cylinder I32 during the indexing movement of the table I3'. When a center drive lathe unit is brought into position. at the loading station R, to receive a rough workpiece, the cylinder I32 is operated to move theloading track I 2'I in toward the right hand tailstock TR, to the broken line position shown in Figure 4. This causes the arm. I42 of the trip stop. M0 to engage the face 98a of the loading rail bracket 98 so as to rotate thetrip stop'tolower the arm MI and allow a crankshaft WR to roll. on to the loading rail 91. The cylinder then is actuated to withdraw the track I21, releasing the arm I42 so that the arm I4l' again swings up due to the downward action of the arm I43, to keep the remaining rough crankshafts WR; in proper position on the loading track for the next loading cycle. The orientation of the chucking V-notches I! about the axis 93a; at

this time is of no importance as the crankshafts chucking andunchucking station L. The crankshaft isthus automatically loaded on the right hand tailstock TR on its loading rail 91, the

crankshaft resting against the surface I45 of the tailstock so that it will be carried while so supported around to the chucln'ng and unchucking station L-with the indexing of the table I3.

Apparatus is provided for automatically removing the finished crankshafts WF from the machine-atthe completion of the machining operation. This arrangement is best shown in Figure 8; and comprises a frame I46 mounted.

on the floor which carries the machine base III. on top of the frame is provided the sloping guideways I47 upon 'which is reciprocatably mounted the unloading track I48 comprising the rails I49 and I50. The unloading track I48 is reciprocated by the fluid pressure operated cylinder I5I fixed to the frame I46 by the bolts I52. This cylinder has a piston rod I53 connected through a link I54 with the lever arm 1 I55"pivotally mounted at I56 on the frame I46.

The upper end of the lever arm I55 is provided with an elongated slot I51 in which operates the pin I58 fixed to the unloading track so that when fluid pressure is appropriately applied to the cylinder, the unloading track may be reciprocated on the ways I41. On the upper raised inner end of the rails I49 and I50 are pivotally mounted at I60 the pickup fingers I59. As the rails are moved to the pickup position indicated in broken lines, the under surface I6I of the pickup fingers engages the edge I62 of the receiving rail bracket causing the fingers to raise up, lifting the crankshaft by its end line bearings and causing it to roll clear of the receiving rail 91 so that it rolls down the rails I49 and I50 until it engages the stop I53 from which it may be removed for subsequent operations. A stop pin I64 holds the fingers I59 in proper operative relationship when the unloading track is moved back to retracted position while the table I3 is rotating in indexing movement. The cylinders I32 and I5I are operated in proper timed relationship with the operation of the table indexing mechanism and the movement of the tailstocks by any well known electrichydraulic control mechanism. Since the details of such control mechanism form no specific part. of this invention, further detailed description of such mechanism isdeemed unnecessary.

One preferred method of operating the machine is as follows: Assuming there have been no crankshaits presented to the machine and that the center drive lathe units A, B, C and D are in the indexed positions shown in Figures 2 and. 2a, the tailstocks of the unit A will be shifted downwardly with the centers 92 on the axis 93 of the center drive ring gears, the loading track cylinder I32 is actuated to move the loading track I2 up against the surface 93a of the right hand tailstock TB. of the unit A to deposit, the first rough crankshaft WR on the receiving rail 91'. Figure 2a and then to withdraw to the. position shown in Figure 2. The table I3 then indexes in the direction indicated by the arrow I in Figure 2a to bring. the unit A. to a. second chucking and unchucking station L. At this station L, the tailstocks shift upwardly to-bring the receiving rails in a position with the work crankshaf-tWR positioned with its linebearing axis 93a on the axis of rotation 93 of the center drive ring gears, Figure 5. The operator rotates the crankshaft manually about its axis 93a, if required, to bring the proper V-notches l? in engagement with the rail 91 on the tailstock TR. With the ring gears stopped, and the chucks in the ring gears open, and with the tools in retracted position, and rails l H32 and H33 swung up to position Hi9, the operator slides the crankshaft WR axially into the chucks to the work machining position WM. The tailstocks are then lowered and the centers 92 engaged, and clamps the chucks on the crankshaft. During this time, another crankshaft has been loaded from the loading track I21 on to the unit B as described for unit A.

The table l3 again indexes to bring unit A to a third unloading station F, while unit B is indexed to the chucking and unchucking station L where another rough crankshaft is put in working position by the operator in the unit B. As the units index with the rotation of the table i3 about its axis l3a from the chucking and unchucking station L to the unloading station E, the center drive crankshaft lathe units start up the center drive ring gears and the tools feed to the work to begin the machining of all the line bearing portions of the crankshafts. As the units index from a first loading station R, the turning operations on the work have been completed, the ring gears and chucks stop rotating, and the tools move back to retracted starting position 58a. From the time the units arrive at the unloading station F, till they leave the loadin or receiving station R, the center drive units are continuously operating to complete all of the line bearing portions of the crankshafts.

After all of the units have been loaded as described, the unit D moves to the chucking and unchucking station L with a crankshaft in the chucks in machining position WM which has just been completely machined, and with a rough crankshaft on the right hand tailstock TR ready to be chucked in operating position in unit D. The tailstocks are then shifted upwardly to bring the rough crankshaft WR in alignment with the chucks. The operator then pushes the rough crankshaft WR axially into machining position WM in the chucks which he have now loosened. This pushes the finished crankshaft W'F out of the chucks on to the receiving rail 9'1 on the left hand taiistock TL, Fig. 2a. The centers $2 are again engaged after shifting the tailstocks downwardly and the chucks clamped on the rough workpiece WR. The table l3 indexes the unit D to the unloading station F where the unloading track iiiis actuated to take the finished crankshaft WF off of the receiving rail 9'! of the left hand tailstock. In this manner, the machine continues to operate, receiving rough crankshafts WR. at the loading or receiving station R and removing finished crankshafts WF at the unloading station F, while the operator is required only to manually slide in and push out the rough and finished crankshafts and to properly chuck the rough crankshafts WR, in machining position WM in the units at the chucking and unchucking station L.

Having thus fully set forth and described this invention, what is claimed is:

1. In a work handling apparatus for a center drive crankshaft lathe having, a right hand and a left hand tailstock vertically reciprocable on said lathe horizontally disposed centers in said 8. tailstocks, a work receiving rail on each of said tailstocks, means for vertically shifting said tailstocks to present either said centers or said receiving rails in operative position in said lathe, means for horizontally loading unmachined crankshafts on a receiving rail of one of said tailstocks comprising a reciprocatable loading track inclined downwardly toward said receiving rail, power means for reciprocating said loading track, a trip stop on the inner lower end of said loading track arranged to engage said receiving rail when in operative position when said loading track is moved toward said tailstock to engage said rail to release an unfinished crankshaft and deposit it on said receiving rail of said one tailstock, and means for removing a finished crankshaft from the receiving rail of said other tailstock comprising, a reciprocatable unloading track inclined downwardly away from said other tailstock, power means for horizontally reciprocating said unloading track, and pickup fingers on the inner raised end of said unloading track adapted to engage said receiving rail on said other tailstock when said unloading track is moved toward and in engagement with said'cther tailstock to remove said finished crankshaft from said receiving rail.

2. In a work handling apparatus for a machine tool having a frame, a movable tailstock, a center and a receiving rail on said tailstock, means for moving said tailstock to present either said center or said receiving rail in operative position in said machine tool, a downwardly and inwardly inclined track including a pair of spaced rails, a loading frame fixed relative to the frame of said machine tool, guideways on said loading frame for reciprocatably carrying said pair of spaced rails, power means interconnected between said spaced rails and said loading frame to reciprocate said spaced rails relative to said tailstock, a trip stop rockably mounted on the inner lower end of said rails, a downwardly depending arm on said trip stop adapted to engage the side of said receiving rail of said tailstock when said receiving rail is moved to operative position, a second upwardly extending arm on said trip stop adapted to engage a workpiece on said spaced rails at a point between said receiving rail and said workpiece, and a third horizontally disposed rearwardly extending arm on said trip stop extending under a workpiece on said spaced rails and engaged by said second arm of said trip stop.

3. In a work handling apparatus for a machine tool having a frame, a movable tailstock, a center and a receiving rail on said tailstock, means for moving said tailstock to present either said center or said receiving rail in operative position in said machine tool, an unloading frame fixed relative to said machine frame, upwardly and rearwardly sloping guideways on said unloading frame, a pair of unloading tracks reciprocatably mounted on said unloading frame, means for reciprocating said tracks, pickup fingers pivotally mounted on the upper inner ends of said rails, stop pin means on said upper inner ends of said rails to position said pickup fingers below the top work engaging surfaces of said tracks, and an abutment surface on the under side of said fingers adapted to engage said receiving rail when in operative position to cause said pickup fingers to be raised upwardly to engage a workpiece on said receiving rail and move said workpiece toward and onto said tracks.

HAROLD J. SIEKMANN. WALTER R MEyER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Richmond Apr.'11, 1899 Pierce May 27, 1902 Muller Jan. 8, 1918 Pew Aug. 6, 1929 Number Name Date Davis Nov. 18, 1930 Bullard Dec. 8, 1931 Smith Feb. 6, 1934 Groene Jan. 26, 1937 Greene Apr. 25, 1939 Greene Aug. 13, 1940 Greene Nov. 12, 1940 Greene July 15, 1941 Delahan Aug. 22, 1944 Davis May 29, 1951 

